Sewing machine presser foot

ABSTRACT

The presser foot has a sole hinged on an intermediate support member which is pivoted on a main support member through a deformable parallelogram of links. The main support has a yoke and screw to clamp the presser foot to the presser bar. A paw may be rigidly fixed to the main support member to hold the fabrics to be sewn when the sole is released. The sole can be drawn in the direction of passage of the fabrics when urged towards the feed dog thereby preventing relative slippage of glossy or binding fabrics. A restoring device is coupled to the needle actuating mechanism to bring the sole back into a neutral position when released.

United States atent [1 1 Robert SEWING MACHINE PRESSER FOOT Ramon CasasRobert, Geneva, Switzerland Assignee: Meiina S.A., Fribourg, SwitzerlandFiled: Feb. 19, 1971 Appl. No.: 117,004

[75] Inventor:

[30] Foreign Application Priority Data Mar. 6, 1970 Switzerland..3302/70 References Cited UNITED STATES PATENTS 1/1971 Seaman ..112/2121 May 22,1973

1,474,966 11/1923 Hayes ..112/212 2,742,009 4/1956 Enos ..112/235Primary Examiner-Patrick D. Lawson AttorneyEmory L. Groff and Emory L.Groff, Jr.

[57] ABSTRACT The presser foot has a sole hinged on an intermediatesupport member which is pivoted on a main support member through adeformable parallelogram of links. The main support has a yoke and screwto clamp the presser foot to the presser bar. A paw may be rigidly fixedto the main support member to hold the fabrics to be sewn when the soleis released. The sole can be drawn in the direction of passage of thefabrics when urged towards the feed dog thereby preventing relativeslippage of glossy or binding fabrics. A restoring device is coupled tothe needle actuating mechanism to bring the sole back into a neutralposition when released.

Pmmmw w 3,734,041 SHEET 1 OF 2 I INVENTOR Rama/v cA-SAS- ROBERT ATTORNEYPATENTED HAY 2 2 I973 SHEEf 2 [IF 2 1N VENTOR ATTORNEY SEWING MACHINEPRESSER FOOT The present invention relates to a sewing machine presserfoot.

The operation of sewing two pieces of fabric to one another by means ofa sewing machine can create certain problems, in particular when thesewing of fabrics very slippery with respect to one another is involved,especially those based on synthetic fibers, such as fine machine-knittedor woven materials or other fabrics or, on the other hand, when fabricswhich slide with great difficulty are concerned, such as rubberizedfabrics, plastics, etc. In fact, it is then observed that only the lowerpiece of fabric, which is directly in contact with the feed dog, isdrawn on uniformly, the upper piece of fabric only following themovement of the lower piece with a delay or with a displacementresulting from the sliding of one piece on the other. In certainindustrial sewing machines, the lower feed dog has been completed by afeed dog arranged above the parts to be sewn and of which the movementis synchronized with the lower feed dog. However, such a devicecomplicates the mechanism of the sewing machine and makes it expensive,which is hardly acceptable for a domestic sewing machine, for example.

It is an object of the present invention to enable, by a simple andinexpensive structure, correct feeding of the pieces of fabric, even inthe difficult cases of fabrics which are too slippery, or on the otherhand, too difficult to slide on one another.

It is another object of the invention to provide an improved presserfoot for a sewing machine, which overcomes the above-mentioneddrawbacks.

To this end, according to the invention, there is provided a presserfoot for a sewing machine comprising a sole for pressing the fabricduring its passage, characterized in that the sole is movable in thedirection of movement of the fabric, this foot comprising a device forrestoring the sole into a neutral position, this device being connectedto the needle actuating mechanism.

In order that the invention may be more fully understood, one embodimentof a presser foot according to the invention is described below, purelyby way of illustrative but non-limiting example, with reference to theaccompanying diagrammatic drawings, in which:

FIG. 1 is a view of said embodiment in side elevation, partly insection, mounted on the presser bar of a sewing machine;

FIG. 2 is a view in front elevation, partly in section, of this presserfoot;

FIGS. 3 to 6 are views similar to that of FIG. 1 showing on a reducedscale the various phases of operation of this presser foot; and

FIG. 7 is a plan view of the latter.

With reference to FIGS. 1 and 2, the machine presser foot shown isassumed to be mounted on a sewing machine of which a portion of the head1 is visible, and also the needle hole plate 2 and the fabric feederclaws or feed dog 3. In this head 1, the needle bar 4 is slidablevertically and bears a needle clamp 5 provided with a neck 6 into whichpasses a fixing screw 7 for the needle 8.

Parallel to the needle bar 4 in the head 1 is arranged a presser bar 9subject to the action of a spring (not shown in the drawing) and tendingto urge this bar 9 downwardly. A lever mechanism of known constructionenables this presser bar 9 to brought into an upper position onpreparing the sewing machine. At its lower part, this presser bar 9 hasa threaded hold 10 inside of which is screwed a fixing screw 11 for thepresser foot proper. This presser foot comprises a clamping member 12constituting a main support, said clamping member having two spurs 13 ina form of a yoke intended to be applied against the lower part of thepresser bar 9. This screw 11 grips by its head the said spurs 13 againstthe presser bar 9. This main support 12 is extended at its lower part bya fixed paw 14 provided with an opening 15 for the passage of the needle8 and a slot 15a for the introduction of the thread.

The sole 16 of this presser foot is hinged with respect to the mainsupport 12, this through the interposition of an intermediate support17. This intermediate support 17 is itself connected to the main support12 through transversal links 18 and 19 pivoted to suspension links 20and 21. This assembly of links 18-21 constitutes a deformableparallelogram comprising a fixed pivoting axle 22 borne by the mainsupport 12, a movable pivoting axle 23, an axle 24 connecting the links20a and 20b to the transverse link 18 and a pivoting axle 25 connectingthe other end of the link 18 to the link 21. A tongs spring 26 isengaged around the pivoting axle 22 and one of its ends 27 is fastenedto the axle 23, while its other end 28 is supported against a part ofthe main support 12 (see FIG 5). This spring 26 therefore tends to makethe deformable parallelogram pivot so as to urge the sole 16 lightlyagainst the parts to be sewn 48, 49. The said sole 16 is hinged to thesupport 17 by pivoting axles 29a and 29b.

The transverse link 19 has a lateral extension 30 on one of the edges ofwhich is arranged a cam 31 The link 20a is rigidly fixed to a folded lug32 provided with an extension in a form of the fork 33, with two teeth,defining between them a notch 34 of V-shape on the opposite edges ofwhich are formed two cam profiles 35 and 36.

The main support 12 bears, in addition, a pivoting axle 37 for a lever38 of which one arm bears a pivoting axle 39 on which a roller 40intended to cooperate with the cam 31, is rotatable. This lever 38 alsobears a finger comprising an axle 41 hearing a roller 42 capable ofcooperating with one or other of the two cam profiles 35 and 36. Anotherarm 43 of this lever 38 has a slot in the form of a slide 44 engagedaround the neck 6 rigidly fixed to the needle clamp 5. This arm 43 ofthe lever 38 is hence integral in movement, through the hinge-slide 44,with the needle bar 4. The upper thread 45 used for sewing has beenshown in the drawing passing through a thread-guide member 46 borne bythe needle clamp 5 and engaged in the eye 47 of the needle 8'.

The operation of the sewing machine presser foot described above withrespect to the drawings is as follows:

This presser foot is accordingly fixed to the presser bar 9 of anordinary sewing machine in the same manner as all presser feet ofconventional construction, by means of clamping screw 11. On assembling,the slide 44 is engaged on the neck 6 rigidly fixed to the needleclamp5. FIG. 1 shows the various members of this presser foot when the need 8is disposed in the vicinity of its highest position with respect to theneedle hole plate 2. In this position, the roller 40 acts on the cam 31and thus pushes back the link 19 in anti-clockwise direction, around theaxle 22, which has the effect of pushing the sole 16 downwardly by meansof the link 21 and the support 17. The latter is therefore held firmlyin contact with he parts to be sewn 48 and 49 which are flattenedagainst the feed dog 3.

During the downward movement of the needle 8 which the first phase isshown in FIG. 3, the roller 40 follows the cam 31 and ends by losing allaction against this cam .31 when it reaches the lower part 50 of thesaid cam 31. During the stitching phase of the needle 8 in the parts tobe sewn 48, 49, which phase shown in FIG. 4, the dog 3 is withdrawnunder the needle-hole plate 2, the roller 40 is without action on thecam 31 and the link 19 respectively, but on the other hand the roller 42is engaged in the V-shaped notch 35 and comes in the contact with one orother of the cam profiles 35 and 36 to cause centering of the sole 16.In fact, this operation of centering is necessary after each stepwiseforward or backward movement of the feed dog 3. The roller 42 thereforeacts through the lug 32 on the link 20a ensuring centering of the sole16 through the interposition of the link 18 and of the support 17. Itshould be noted that during the phase represented in FIG. 4, the paw 14supports the parts to be sewn 48, 49 around the hole for the passage ofthe needle 8.

On the re-ascending stroke of the needle 8, which stroke is shown inFIG. 5, the lever 38 is driven to more in clockwise direction and assoon as the needle 8 has left the parts to be sewn 48 and 49, and thefeed dog 3 starts to project through the needle-hole plate 2, the roller40 by cooperating with the cam 31 tilts the link 19 in anticlockwisedirection, which forces downwards the link 21, the pivoting axle 25, theintermediate support 17, the axle 29a, 29b, and thus the presser foot 16against the feed dog 3. The sole 16 is hence held firmly applied againstthe parts to be sewn 48 and 49 which are gripped between this sole l6and the feed dog 3 preventing any sliding between these two parts 48 and49. During this pressing movement of the sole 16 against the feed dog 3,the presser bar 9 is pushed back upwardly against the action of itspressure spring arranged in the head 1 of the sewing machine thusdisengaging the paw 14 on the parts to be sewn 48, 49.

FIG. 6 shows thepositions occupied by the various members of the presserfoot, when the feed dog 3 of the sewing machine actuates a recoilmovement of the parts to be sewn 48, 49 with respect to the needle holeplate 2. FIG. 6 shows clearly how the sole 16 is then driven towards theleft, with respect to this figure, by the feed dog 3, while the roller40 acts on the cam 31 to apply said sole 16 against the parts to besewn. As soon as the needle 8 is re-engaged in the parts to be sewn 48,49, the feed dog 3 being withdrawn under the needle-hole plate 2, thesole 16 will again be free of any heavy pressure, apart from thatresulting from the spring 26 and the roller 42 will be engaged in thenotch 19 to cause re-centering of the sole 16 with respect to the needle8.

Numerous variations of the presser foot described above could beenvisaged. Thus, the device for transmitting movement between the needleactuating mechanism 8 and the deformable parallelogram 18-21, instead ofbeing constituted by the lever 38 driven by the neck 6, could be formedby any other transmission mechanism acting directly, from drivemechanism ar-- ranged in the head I, on the said deformableparallelogram 18-21. In the example described above with regard to thedrawings, the link 18 constitutes one and the same part with theintermediate support 17. However, it is clear that the intermediatesupport 17 could be constituted by a part coupled or rigidly fixed tothe link 18 or another part of the deformable parallelogram 18-21,especially the link 21 or the axle 25. All such changes andmodifications in the embodiment described above are to be regarded aswithin the scope of the invention as defined by the appended claims.

I claim:

1. In a sewing machine, a presser foot, a feed dog, a presser bar and aneedle-actuating mechanism, said presser foot comprising a sole forpressing fabric during its passage, means coupling said sole to thepresser bar so as to be movable in the direction of movement of thefabric, a device for restoring the sole into a neutral position, saidrestoring device being connected to the needle-actuating mechanism, saidcoupling means comprising an intermediate support on which the sole ispivoted, a main support to which said intermediate support is pivoted,links arranged as a deformable parallelogram constituting said pivot,wherein said restoring device comprises a motion transmitting devicearranged between the needle actuating mechanism and said deformableparallelogram to cause a lowering of the sole against the feed dogduring the phase of passage, so that the parts of fabric to be sewn aregripped between the feed dog and the sole and are drawn in translationmovement by the feed dog, the sole following said translation movement.

2. A sewing machine according to claim 1, wherein the motiontransmitting device comprises a lever pivotally mounted on the mainsupport, a control cam with which one arm of the lever cooperatesrigidly fixed to one of the links forming the deformable parallelogram,while the other arm of said lever is integral in movement with theneedle bar through a sliding pivot.

3. A sewing machine according to claim 2, including a paw rigidly fixedto the main support and arranged to hold the parts to be sewn when thesole is released.

4. A sewing machine according to claim 2, wherein one of said linksbears a centering cam, and a finger on said lever cooperates with saidcentering cam on each downward stroke of the needle, to center the solewhen the latter is released.

5. A sewing machine according to claim 1, including a paw rigidly fixedto the main support and arranged to hold the parts to be sewn when thesole is released.

6. In a sewing machine, a presser foot, a feed dog, a presser bar and aneedle-actuating mechanism, said presser foot comprising a sole forpressing fabric during its passage, means coupling said sole to thepresser bar so as to be movable in the direction of movement of thefabric, a device for restoring the sole into a neutral positioncomprising a centering cam, and a lever pivotally mounted on saidcoupling means and cooperating with said centering cam on each downwardstroke of the needle, to center the sole when the latter is released.

7. A sewing machine according to claim 6, wherein the centering camcomprises a double profile forming opposite edges of a V-shaped notch, afinger on said lever cooperating with one or the other of the edges ofsaid notch according to whether the feed dog actuates a forward orbackward movement of the parts to be sewn.

8. A sewing machine according to claim 6, wherein the centering camcomprises a double profile forming opposite edges of a V-shaped notch, afinger on said lever cooperating with one or the other of the edges ofsaid notch according to whether the feed dog actuates a forward orbackward movement of the parts to be sewn.

9. A sewing machine according to claim 6, including a paw rigidly fixedto the main support and arranged to hold the parts to be sewn when thesole is released.

1. In a sewing machine, a presser foot, a fEed dog, a presser bar and aneedle-actuating mechanism, said presser foot comprising a sole forpressing fabric during its passage, means coupling said sole to thepresser bar so as to be movable in the direction of movement of thefabric, a device for restoring the sole into a neutral position, saidrestoring device being connected to the needle-actuating mechanism, saidcoupling means comprising an intermediate support on which the sole ispivoted, a main support to which said intermediate support is pivoted,links arranged as a deformable parallelogram constituting said pivot,wherein said restoring device comprises a motion transmitting devicearranged between the needle actuating mechanism and said deformableparallelogram to cause a lowering of the sole against the feed dogduring the phase of passage, so that the parts of fabric to be sewn aregripped between the feed dog and the sole and are drawn in translationmovement by the feed dog, the sole following said translation movement.2. A sewing machine according to claim 1, wherein the motiontransmitting device comprises a lever pivotally mounted on the mainsupport, a control cam with which one arm of the lever cooperatesrigidly fixed to one of the links forming the deformable parallelogram,while the other arm of said lever is integral in movement with theneedle bar through a sliding pivot.
 3. A sewing machine according toclaim 2, including a paw rigidly fixed to the main support and arrangedto hold the parts to be sewn when the sole is released.
 4. A sewingmachine according to claim 2, wherein one of said links bears acentering cam, and a finger on said lever cooperates with said centeringcam on each downward stroke of the needle, to center the sole when thelatter is released.
 5. A sewing machine according to claim 1, includinga paw rigidly fixed to the main support and arranged to hold the partsto be sewn when the sole is released.
 6. In a sewing machine, a presserfoot, a feed dog, a presser bar and a needle-actuating mechanism, saidpresser foot comprising a sole for pressing fabric during its passage,means coupling said sole to the presser bar so as to be movable in thedirection of movement of the fabric, a device for restoring the soleinto a neutral position comprising a centering cam, and a leverpivotally mounted on said coupling means and cooperating with saidcentering cam on each downward stroke of the needle, to center the solewhen the latter is released.
 7. A sewing machine according to claim 6,wherein the centering cam comprises a double profile forming oppositeedges of a V-shaped notch, a finger on said lever cooperating with oneor the other of the edges of said notch according to whether the feeddog actuates a forward or backward movement of the parts to be sewn. 8.A sewing machine according to claim 6, wherein the centering camcomprises a double profile forming opposite edges of a V-shaped notch, afinger on said lever cooperating with one or the other of the edges ofsaid notch according to whether the feed dog actuates a forward orbackward movement of the parts to be sewn.
 9. A sewing machine accordingto claim 6, including a paw rigidly fixed to the main support andarranged to hold the parts to be sewn when the sole is released.